voluntary system of certification 自愿认证制

voluntary nervous system 自主神经系统

the voluntary system change 诱致性制度变迁

voluntary voter registration system 选民自愿登记制度

voluntary accountability system 自愿社会问责体系

voluntary quota system 自愿配额制

spontaneous reporting system voluntary 自愿呈报制度

voluntary reporting system 自愿报告系统

system of voluntary service 志愿兵役制

voluntary mutual system 自愿互保制